Breaking the type system needs temporary?

[simendsjo]

On 25.06.2011 19:44, David Nadlinger wrote:
> The result of a cast is not an lvalue.
>
> David
>
>
> On 6/25/11 7:37 PM, simendsjo wrote:
>> I'm calling functions using ParameterTypeTuple. The problem arise when
>> the parameters is defined as const/immutable. So I need to break out of
>> the type system.
>> But I cannot seem to do this without using a temporary variable. Am I
>> doing something wrong?
>>
>> int i = 1;
>> const(int*) c;
>> //c = &v; // ok - cannot modify const
>> int* cp = cast(int*)c;
>> cp = &v; // ok - breaking type system
>> //(cast(int*)c) = &v; // cannot modify const - shouldn't this work as
>> above?
>

So the error message is "wrong"? The error message be something like 
"(cast(int*)c) is not an lvalue"?